TY  - JOUR
A1  - Bassam, Rasha
A1  - Hescheler, Jürgen
A1  - Temiz Artmann, Aysegül
A1  - Artmann, Gerhard
A1  - Digel, Ilya
T1  - Effects of spermine NONOate and ATP on the thermal stability of hemoglobin
JF  - BMC Biophysics
N2  - Background
Minor changes in protein structure induced by small organic and inorganic molecules can result in significant metabolic effects. The effects can be even more profound if the molecular players are chemically active and present in the cell in considerable amounts. The aim of our study was to investigate effects of a nitric oxide donor (spermine NONOate), ATP and sodium/potassium environment on the dynamics of thermal unfolding of human hemoglobin (Hb). The effect of these molecules was examined by means of circular dichroism spectrometry (CD) in the temperature range between 25°C and 70°C. The alpha-helical content of buffered hemoglobin samples (0.1 mg/ml) was estimated via ellipticity change measurements at a heating rate of 1°C/min.

Results
Major results were:
1) spermine NONOate persistently decreased the hemoglobin unfolding temperature T u irrespectively of the Na + /K + environment,
2) ATP instead increased the unfolding temperature by 3°C in both sodium-based and potassium-based buffers and
3) mutual effects of ATP and NO were strongly influenced by particular buffer ionic compositions. Moreover, the presence of potassium facilitated a partial unfolding of alpha-helical structures even at room temperature.

Conclusion
The obtained data might shed more light on molecular mechanisms and biophysics involved in the regulation of protein activity by small solutes in the cell.
KW  - Nitric Oxide Donor
KW  - NONOate
KW  - Circular Dichroism
KW  - Nitric Oxide
Y1  - 2012
U6  - http://dx.doi.org/10.1186/2046-1682-5-16
SN  - 2046-1682
VL  - 5
PB  - BioMed Central
CY  - London
ER  - 
TY  - JOUR
A1  - Bassam, Rasha
A1  - Digel, Ilya
A1  - Hescheler, Jürgen
A1  - Temiz Artmann, Aysegül
A1  - Artmann, Gerhard
T1  - Effects of spermine NONOate and ATP on protein aggregation: light scattering evidences
JF  - BMC Biophysics
Y1  - 2013
U6  - http://nbn-resolving.de/urn/resolver.pl?10.1186/2046-1682-6-1
SN  - 2046-1682
SP  - 1
EP  - 14
PB  - BioMed Central
CY  - London
ER  - 
TY  - JOUR
A1  - Arinkin, Vladimir
A1  - Digel, Ilya
A1  - Porst, Dariusz
A1  - Temiz Artmann, Aysegül
A1  - Artmann, Gerhard
T1  - Phenotyping date palm varieties via leaflet cross-sectional imaging and artificial neural network application
JF  - BMC bioinformatics
N2  - Background
True date palms (Phoenix dactylifera L.) are impressive trees and have served as an indispensable source of food for mankind in tropical and subtropical countries for centuries. The aim of this study is to differentiate date palm tree varieties by analysing leaflet cross sections with technical/optical methods and artificial neural networks (ANN).

Results
Fluorescence microscopy images of leaflet cross sections have been taken from a set of five date palm tree cultivars (Hewlat al Jouf, Khlas, Nabot Soltan, Shishi, Um Raheem). After features extraction from images, the obtained data have been fed in a multilayer perceptron ANN with backpropagation learning algorithm.

Conclusions
Overall, an accurate result in prediction and differentiation of date palm tree cultivars was achieved with average prediction in tenfold cross-validation is 89.1% and reached 100% in one of the best ANN.
Y1  - 2014
U6  - http://dx.doi.org/10.1186/1471-2105-15-55
SN  - 1471-2105
VL  - 15
IS  - 55
SP  - 1
EP  - 8
ER  -